This invention relates to fastener arrangements for joining or separating articles at their edges or surfaces, particularly of the flexible type.
Slide fasteners serving for a repeated joining and separating of two flexible edges are well known. The joining and the separating is effected by means of a shift of the boundary between the zones of the joined state and separated state. At least for the joining operation a slide member has to be operated which is associated with the above-mentioned boundary and which joins, or respectively, separates the two halves of the slide fastener. In widely known cases of use, for example in slide fasteners for apparel, the slide member is manually operated. This, however, gives rise to difficulties if the slide fastener extends into zones that are not easily accessible. Further, there is likely to occur an undesired pinching of material between the slide member and the slide fastener halves. The occurrence of such pinching is enhanced by the fact that joining is brought about by a force exerted on the slide member in a longitudinal direction. As a result, folds are formed in the material of the apparel exactly at locations where they tend to obstruct such joining and may be pinched between the slide fastener halves. This situation is further worsened by the often occurring, reflex-like reaction of the operating person, in that an increased force of short period is applied.
Slideless, flexible magnetic fasteners for apparel are known. In connection with these structures the possibility has also been considered to connect manually only at one location the cooperating parts of the fastener halves to be connected to one another; the connecting process then propagates by itself. In this connection reference is made to the disclosures in U.S. Pat. Nos. 2,627,097 and 3,008,209.
Embodiments of the above-outlined arrangements, however, have not been widely used, probably, because the generated forces were found to be too weak and/or the manufacturing costs too high. Further, it appears that fasteners of the above-outlined type are used primarily with overlapping fabric portions. In these structures the substantial opening forces which are oriented parallel to the fabric surfaces are resisted additionally or principally by means of a mechanical interference due to a proper design of the surfaces.
It was found to be desirable to make fasteners of a simpler structure and, preferably, of unitary material, wherein the state of connection propagates by itself.